Spool with means for start wire insulation

ABSTRACT

A spool formed of insulating material having two end flanges axially spaced apart on a core for carrying a wire coil, one end flange containing a slot and flap, the flap being foldable against the end flange to protect a lead-in end of the wire coil which passes through the slot and is positioned between the flap and the flange.

United States Patent 11 1 1111 3,739,312 Knebel 1451 June 12, 1973 [54] SPOOL WITH MEANS FOR START WIRE 3,453,575 7/1969 Davis 336 192 INSULATION 3,095,635 7/1963 Laviana .L ..336/l9,2 X

' Inventor:

' Assignee: General William J. Knebel, Waynesboro, Va.

Electric Waynesboro, Va.

Filed: June 19, 1972 Appl. No.: 264,002

Corporation,

US. Cl 336/192, 242/l25.1, 336/208 Int. Cl H0lf 15/10, HOlf 27/30 Field of Search 336/192, 198,208;

References Cited UNITED STATES PATENTS 9/1966 Sloan, Jr. 336/192 UX Primary Examiner-Thomas J. Kozrna Attorney wMichael Masnik, Frank L. Neuhauser, Oscar B. Waddell et a1.

[5 7] ABSTRACT A spool formed of insulating material having two end flanges axially spaced apart on a core for carrying a wire coil, one end flange containing a slot and flap, the

flap being foldable against the end flange to protect a lead-in end of the wire coil which passes through the slot and is positioned between the flap and the flange.

9 Claims, 6 Drawing Figures BACKGROUND OF THE INVENTION Inductive assemblies comprising coils of wire mounted on insulative spools are used for a multiple of purposes in today s electronic society. The high volume demand for and consequent high volume production of inductive assemblies means that the slightest reduction in material used or the smallest increase in efficiency of production can result in a vast overall dollar savings. As a result, industry has developed high-speed machines for' automatically winding wire on spools as quickly and accurately as currently possible.

A problem has historically existed, however, in protecting the lead-in end of the coil of wire from electrical contact with the end section of the coil formed by subsequent layers of windings on the spool. Initially, the lead-in end was first run into the spool along the inside surface of one end flange and a piece of insulating tape or film was placed over the wire to protect the leadin end from electrical contact with the end of the subsequently wound coil. However, the tape or film is tedious to install manually and no known automatic winding machine can economically install the tape or film at a high enough speed, especially on very small spools. Furthermore, the tape or film represents additional material which must be figured into overall cost and the tape or film tends to interfere with efficient coil winding.

Since the turn of the century, slots have been cut into one end flange through which the lead-in end of wire is brought inside the spool. This procedure provides effective insulation of the lead-in end of wire from the coil, but the lead-in end of wire becomes exposed to any electrical or structural parts adjacent the spool such as a mounting assembly or frame in which the spool is ultimately positioned.

Various modifications have recently been attempted to protect the lead-in end of wire from unwanted external contact. One modification teaches the use of a molded flange formed with a pocket adjacent the flange slot in which pocket the lead-in end of wire is positioned and protected both from parts external to the spool and the coil wound on the spool. This type of modification has only limited effectiveness since the pocket is difficult to mold. The pocket uses up valuable winding space and the operation of positioning the lead-in wire into the pocket is oftentimes difficult to-accomplish. Hence, the need currently exists for a spool structure: which insulates a lead-in end of wire from both internal and external electrical contact; which does not require extra pieces of insulation; which isre'latively easy and inexpensive to build; which uses up very little space; and whichis readily adaptable for use with currently existing automatic coil winding machines.

SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to provide a spool with improved means for providing lead-in wire insulation.

It is another object of the present invention to .provide a spool with improved means for providing lead-in wire insulation without the need to employ extra pieces of insulation.

It is a further object of the present invention to pro vide a spool with improved means for providing lead-inwire insulation, which spool is easy and inexpensive to mold.

It is still a further object of the present invention to provide a spool with improved means for providing lead-in end of wire insulation, which spool is readily adaptable for use with currently existing automatic coil winding machines.

One preferred embodiment of the present invention comprises an insulating spool having first and second flanges axially spaced from one another on an elongated core to define a winding space on the core for supporting a coil of wire. The first flange contains an opening which provides a passageway for a lead-in end of wire from exterior the spool through the first flange into the winding space. To accomplish the above objectives, the spool further comprises a flap hingeably attached to the outside surface of the first flange adjacent the opening. The flap has an open position in which the opening is readily accessible from exterior the spool and a closed position in which the flap lies against the outside surface of the first flange whereby the lead-in end of wire extending through the opening into the winding space maybe positioned between the outside surface of the first flange and the flap.

In another embodiment of the present invention, the flap includes an extended member which lies across the top of the wire coil and rests on the peripheral edges of the first and second flanges when the flap is in the closed position. The second surface thereby provides a structural element on which an electrically conductive terminal is positioned to receive the lead-in and leadout ends of the wire coil.

BRIEF DESCRIPTION OF THE DRAWINGS For a fuller understanding of the present invention,

reference is made to the detailed description belo when taken with the drawings wherein:

- FIG l is an isometric view of one embodiment of the present invention;

FIG. 2 is an orthogonal view of the embodiment disclosed in FIG. 1;

DETAILED DESCRIPTION OF THE INVENTION FIG. I discloses aspool II) of an electrical insulating material such as molded plastic "having :firstand second flanges 12 and l t-axially spaced apart'on an elongated core 16. Inside surfaces A-of firstand second flanges 12 and 14 and core l6 define a w'indingsapce 17 in which a coilof wire may be wound, utilizingautomated winding machines'as are well known to those skilled in the artof assembling inductive'devices. The flanges l2 and 14in defining the winding space 17 may take on any shape that :is necessary to facilitate the use of automated winding machines provided that each flange 1'2 and l4-has an inside surface A and an outside surface B. First and second 'flanges l2 and 14in FIG. 1 are shown to assume'a circular shapemerely to provide an illustration of one shape commonly used with automated winding machines.

In order to provide a pathway from the exteriorof spool 10 to the winding space 17 in which a wire coil is formed, an opening or aperture 18. is formed in first flange 12. The opening 18 extends completely through first flange 2 from the .outside surface B to the inside surface A to provide a pathway from exterior the spool through first flange 12 to the winding space 17. In FIG. 1, oepning 18 is shown to assume a slot-like shape starting at a peripheral edge of first flange 12 and extending inwardly toward thecore 16. This particular configuration for openig 18 is provided only as an illustrative example. Different shaped op'enings may also provide suitable passageways. Forexample, opening 18 instead of lying in a radial direction as shown in FIG. 1 may lie in a portion of a cord of first flange 12. In the alternative, opening 18 may merely comprise a hole in first flange l2 and not extend outward so as to break the peripheral edge of first flange 12 as shown in FIG. 1.

A flap 20 is shown hingeably attached to the outside surface B of. first flange l2. Flap 20'is movable 'to'assume a first open position whereby opening 18' is readily accessible. from exterior the spool anda second closed position whereby flap 20 lies adjacent outside surface Bof first flange 12 to provide insulative protection for anywire passing through opening 18 from contact with objects adjacent outside surface B of first flap l2.

In the particular embodiment shown in FIG. 1, flange 20 is hinged along an axis 22, which axis 22 defines a chord of first flange 12 and which cord is positioned tangent the base 24 of opening 18. This embodiment provides suitable protection for a lead-in wire which extends from opening 18 to a peripheral edge of first flange 12. This particular embodiment also readily lends itself to construction by plastic molding. The axis 22 of flap 20, however, is not to be limited to a chord as shown in FIG. 1. For example, the axis 22 of flap 20 may run parallel to the longitudinal axis of the opening 18 and thereby also provide suitable protection for any lead-in wire passing through opening 18.

The size of spool 10 and the dimensions of first flange 12, opening 18, and flap 20 are not intended to be fixed by the one preferred embodiment disclosed, but rather are intended to be adapted for use with various size spools used in the assembly of inductive devices. However, the present invention is particularly effective in the assembly of a very small inductive spool. For example, dimensions illustrated by FIG. 2 of the drawings and the following table represent a molded spool which has already been proven capable of economic and efficient mass production: m=.l45 inch; n=.008 inch; o=.004 inch; p=.004 inch; q=.012 inch; r=.035 inch; s=.072 inch; t'.205 inch; u=.006 inch; v=.06v inch; w=.076 inch. It should be noted that by limiting the. width of first -flange 12 which is to lie under flap 20 to one-half the width (0.004 inch) of the remainder of first flange 12 (0.008 inch) and dimensioning flap 20 to have a w idth (0.004 inch) also equal to one-half the width of the remainder of first flange 12, then the construction of a spool incorporating the present invention will not require any additional material over' that required by a prior art spool of similarsize. Again, it is, of course, un'- derstood that the present invention is not limited to the above given dimensions;

In practicing the present invention disclosed in FIGS. 1 and 2, spool 10 is formed byany suitable plastic molding process known to those skilled in the art. Since no pocket or complicated groo've need be formed, almost any known molding process can be used. In a preferred assembly, flap 20 is initially biased in a first position whereby hole 18 is readily accessible from exterior spool 10. A lead-in end of wire to be wound on core 16 is passed from exterior spool 10 through opening 18 into the winding space 17. The wire is then wound on core 16 a desirednumber of turns as is well known to those skilled in the art of manual or automatically wound inductive devices. Upon assembly of the coil 10 into a suitable frame holder, the flap 20 is forced into a second position whereby it lies adjacent outside surface B of first flange 12 and thereby provides protection for the lead-in wire from contact with the frame or any other external apparatus.

FIGS. 3 and 4 disclose a modification of the embodiemnt taught in FIGS. 1 and 2. In FIGS. 3 and 4 spool 10 again comprises first and second flanges 12 and 14 axially spaced along coil 16 to define a winding space 17 therebetween. In FIGS. 3 and 4, however, flap 20 has an extended member or second surface 26 whcih is positioened at an angle to a first surface defining flap 20. The length of extended member 26 and the angle member 26 makes with flap 20 may be chosen, as shown in, FIGS. 3 and 4, such that member 26 bridges the peripheral edges of first and second flanges 12 and 14 when flap 20 is in the closed second position.

Conductive contact terminals 28 and 29 are shown mounted on member 26. The contacts may comprise metal deposition or any other suitable means for providing external circuit connections.

In opration of the embodiment of the present invention disclosed in FIGS. 3 and 4, spool 10 is formed of plastic molded material, such as nylon and other comparable materials well known to those skilled in the molding art. Flap 20 is initially biased in an open first position enabling opening or aperture 18 to provide a passageway for a lead-in wire 31 from extenral spool 10 through first flange 12 to the winding space of coil 10. The remaining portion of the wire is then coiled around core 16 either manually or by an automatic winding machine as is readily known to those skilled in the art until a satisfactory number of layers have been wound on core 16.

The spool 10 may then be placed in a suitable framing member illustrated by supports 30 in FIG. 4. As coil 10 is placed between supports 30, flap 20 is forced from the open first position to a closed second position whereby the lead-in end of the wire 31 extending from the winding space through the opening 18 is positioned between the outside surface of the first flange l2 and the flap 20 to protect it from contact with support members 30 or any other external apparatus. The other end or lead-out end 32 of the wire wound on core 16 is passed from the winding space 17 between the first and second flanges l2 and 14 and connected to the conductive contact terminal 28 thereby providing a readily accessible external circuit connection. A second conductive contact terminal 29 may be similarly provided for external connection to the lead-in wire 31. Leads 33 and 34 provide the connections to outside circuitry.

Having described two specific embodiments of a spool with means for lead-in wire installation, it is to be understood that various changes may be made in detail within the scope of the claims without departing from the spirit of the invention. It is, therefore, to be understood that the invention is not to be limited to the specific details shown and described.

What I claim as new and desire to secure by Letters Patent of. the United States is:

l. A spool for mounting a coil of wire comprising:

an elongated core; first and second flanges axially spaced from one another on said core, said first and second flanges having inside surfacesv which define a winding space on said core for supporting said coil of wire;

said first flange having an opening extending from said inside surface to an outside surface of said first flange; and

a flap hingeably attached to said outisde surface along an axis defined by a chord of said flange of said first flange adjacent said opening, said flap having an open position in which said opening is accessible from the outside side of said first flange and a closed position in which said flap lies against said outside surface and overlies said opening whereby a lead-in end ofa wire extending from said winding space, through said opening may be positioned between the outside surface of said first flange and said flap.

2. The spool claimed in claim 1 wherein said first flange and said flap comprise a single piece of molded plastic.

3. The spool claimed in claim 2 wherein said opening forms a break in a peripheral edge of said first flange,

4. The spool claimed in claim 1 including a member extending from and at an angle to said flap such that said member lies across said first and second flanges when said flap is in said closed position, said member providing a means for supporting external connections.

5. A structure for insulating the lead-in end of a wire coil from the lead-out end of a wire coil comprising a spool for mounting the wire coil, said spool comprising an elongated core, first and second flanges axially spaced from one another on said core, said first and second flanges having inside surfaces which define a winding sapce on said core for supporting said wire coil, said first flange having an opening extending from said inside surface to an outside surface of said first flange, said spool being formed of an insulating material, a flap of insulating material extending from said first flange from an axis defined by a chord therof and saidflap having first and second surfaces positioned at an angle to one another, said flap having an open position in which said flap forms an angle with said outside surface and a closed position in which said first surface of said flap lies against said outside surface of said first flange and overlies said opening whereby said lead-in end of wire extending from said winding space and.

passing through said slot may be positioned between the outer surface of said first flange and the first surface of said flap and wherein in said closed position said second surface of said flap lies across the wire coil and rests on peripheral edges of said first and second flanges.

6. A structure according to claim 4 further comprising means providing at least one conductive contact terminal on at least one surface of said flap for connecting thereto the external connections of said wire coil.

7. A spool formed of insulating material comprising two end flanges spaced apart on a core for carrying a wire coil, one portion of one end flange containing a slotted sector and a separate but abutting flap sector overlying said slotted sector, said flap sector being moveable about an axis defined by a chord of said one flange such that in an open position a lead-in end of the wire coil may be passed through the slotted sector, whereas in a closed position the passed lead-in wire is covered by said flap sector overlying said slotted sector.

8. A spool formed of insulating material comprising two end flanges spaced apart on a core for carrying a wire coil, one sector of one end flange essentially being divided to comprise a slotted sector and a separate but abutting flap sector overlying said slotted sector, said flap sector being hingeably attached to said slotted sector along an axis on said one flange such that in an open position a lead-in end of the wire coil may be passed through the slotted sector, whereas in a'closed position the passed lead-in wire is covered by said flap sector overlying said slotted sector.

9. A spool formed of insulating material comprising two end flanges spaced apart on a core for carrying a wire coil, one end flange having a sector defined by a chord and the periphery beyond said chord, said sector being divided into a component slotted sector and a component flap sector overlying said slotted sector, said flap sector being moveable about an axis defined by said chord such that in an open position a lead-in end of the wire coil may be passed through the slotted sector, whereas in a closed position the passed lead-in wire is covered by said flap sector overlying said slotted I 111 111131) STATES PATENT owner v CERTIFICATE @F CURRECTION 3,739 .312 Datd June 12 1973 Patent No.

d 'William J, Knebel It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below;

" On title page, linev y starting with [73] Assignee: after .Ge'neral Electric" cancel "Corporation" and insert Company column 3', line ,3 cancel "2-" and insert 12 line I I} cancel "openig" and insert opening Column 4} lines 16 & l7 fcancel embodiemnt" and. insert I .7 I --r*' embodiment I line- 22 I cancel "whcih" and insert which cancel "positi0ened and insert positioned line 32: cancel "opration" and insert -v operation lin'ef38 I I cancel 'extenral" and insert external I Claim S, {line 41 f cancel "sapce'" and insert space Signed anti sealed this 'l9th -day of November .1974.

(SEAL) I Attest; I

MCCOY M. GIBSON JR, c. MARSHALL DANN Arresting Officer. Commissioner of Patents FoRn P0-1050 (10-69) I USCOMWDC 603mm U.S. GOVERNMENT PRINTING OFFICE: I969 0-366-335 3,739 ,312 Bat-ed June 12 1973 Patent No.

inventor) William J. Kn'ebel It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

On title page, line starting with [73] Assignee: after .General Electric" cancel "Corporation" and insert Company g a i Column 3, line 3 cancel "2-" and insert l2 line 9' V cancel "openig" and insert opening Column 4} lines 16 & l7 cancel "embodiemnt and insert I embodiment I ,line "22 cancel "whcih" and insert cancel "positioened" and insert positioned line 32 I cancel "opration" and insert operation line 38 cancel "extenral" and insert external Claim 5, "line 41 1 cancel "sapce'" and insert space Signed and sealed this Nth-day of November 1974 (SEAL) Attest:

McCOY M. GIBSON JR. Y C. MARSHALL DANN Attesting Officer. Commissioner of Patents FORM po'wso USCOMM-DC suave-ps9 [1.5. GOVERNMENT PRINTING OFFlCEI 959 -356-334 

1. A spool for mounting a coil of wire comprising: an elongated core; first and second flanges axially spaced from one another on said core, said first and second flanges having inside surfaces which define a winding space on said core for supporting said coil of wire; said first flange having an opening extending from said inside surface to an outside surface of said first flange; and a flap hingeably attached to said outisde surface along an axis defined by a chord of said flange of said first flange adjacent said opening, said flap having an open position in which said opening is accessible from the outside side of said first flange and a closed position in which said flap lies against said outside surface and overlies said opening whereby a leadin end of a wire extending from said winding space, through said opening may be positioned between the outside surface of said first flange and said flap.
 2. The spool claimed in claim 1 wherein said first flange and said flap comprise a single piece of molded plastic.
 3. The spool claimed in claim 2 wherein said opening forms a break in a peripheral edge of said first flange.
 4. The spool claimed in claim 1 including a member extending from and at an angle to said flap such that said member lies across said first and second flanges when said flap is in said closed position, said membeR providing a means for supporting external connections.
 5. A structure for insulating the lead-in end of a wire coil from the lead-out end of a wire coil comprising a spool for mounting the wire coil, said spool comprising an elongated core, first and second flanges axially spaced from one another on said core, said first and second flanges having inside surfaces which define a winding sapce on said core for supporting said wire coil, said first flange having an opening extending from said inside surface to an outside surface of said first flange, said spool being formed of an insulating material, a flap of insulating material extending from said first flange from an axis defined by a chord therof and said flap having first and second surfaces positioned at an angle to one another, said flap having an open position in which said flap forms an angle with said outside surface and a closed position in which said first surface of said flap lies against said outside surface of said first flange and overlies said opening whereby said lead-in end of wire extending from said winding space and passing through said slot may be positioned between the outer surface of said first flange and the first surface of said flap and wherein in said closed position said second surface of said flap lies across the wire coil and rests on peripheral edges of said first and second flanges.
 6. A structure according to claim 4 further comprising means providing at least one conductive contact terminal on at least one surface of said flap for connecting thereto the external connections of said wire coil.
 7. A spool formed of insulating material comprising two end flanges spaced apart on a core for carrying a wire coil, one portion of one end flange containing a slotted sector and a separate but abutting flap sector overlying said slotted sector, said flap sector being moveable about an axis defined by a chord of said one flange such that in an open position a lead-in end of the wire coil may be passed through the slotted sector, whereas in a closed position the passed lead-in wire is covered by said flap sector overlying said slotted sector.
 8. A spool formed of insulating material comprising two end flanges spaced apart on a core for carrying a wire coil, one sector of one end flange essentially being divided to comprise a slotted sector and a separate but abutting flap sector overlying said slotted sector, said flap sector being hingeably attached to said slotted sector along an axis on said one flange such that in an open position a lead-in end of the wire coil may be passed through the slotted sector, whereas in a closed position the passed lead-in wire is covered by said flap sector overlying said slotted sector.
 9. A spool formed of insulating material comprising two end flanges spaced apart on a core for carrying a wire coil, one end flange having a sector defined by a chord and the periphery beyond said chord, said sector being divided into a component slotted sector and a component flap sector overlying said slotted sector, said flap sector being moveable about an axis defined by said chord such that in an open position a lead-in end of the wire coil may be passed through the slotted sector, whereas in a closed position the passed lead-in wire is covered by said flap sector overlying said slotted sector. 